At present, the endourologic treatment of urinary calculosis provides for the introduction, within the operating channel of specific endoscopes, of tools useful for the treatment of calculosis itself. These tools are essentially divided into two types: those adapted to reduce the stone in a series of fragments of suitable dimensions suitable for natural extraction by the human body, and those aimed at mobilizing the stone itself or at the direct extraction of the fragments.
Among the devices of this second type are grippers specifically designed to grab the stone fragments. In particular, the largest endoscopes, with a rigid structure, allow the use of very large grippers, which are particularly effective in terms of grip and extraction. Moreover, also small endoscopes, with a flexible structure, allow the passage of small grippers within their operating channel.
While grippers are economically advantageous in that, after sterilization, can be reused, they are nevertheless ineffective in most cases. In particular, the grippers, due to their specific conformation as well as to the material of which they are made, once introduced inside the endoscope cause the stiffening of the latter and a reduction in its flexibility. This greatly affects the effectiveness of the endoscope itself, limiting its ability to reach peripheral areas of the urinary tract, especially in cases where the target stone is “out of axis”, that is, misaligned with respect to the entrance of the endoscope.
Moreover, the operation of the grippers is compromised beyond a certain curvature thereof. In particular, beyond a certain limit value, the angularity of the bearing structure compromises the transmission of the mechanical control from the handpiece to the clamps of the grippers, thereby preventing the opening of the mouth thereof.
As an alternative to grippers, among the devices aimed at mobilizing the stone and/or at the direct extraction of the fragments thereof, the so-called baskets are also known. These are extremely thin and flexible devices that can be introduced into the body through the endoscope's operating channel. They are manouvrable through an outer handpiece that controls the opening of metal coils on the lithiasic fragment. In particular, such coils, by reclosing themselves as a network on the target stone fragment, envelop it so as to allow the mobilization or extraction thereof.
The basket devices overcome all the drawbacks of grippers since, having a thinner structure, they compromise the flexibility of the endoscope in which they are introduced to a lesser extent. In addition, unlike the grippers, they can open on the target even under highly angled conditions.
However, also the basket devices are not completely satisfactory. Firstly, being disposable devices, they add a specific cost to each surgical procedure. In addition, it is often difficult to block the stone fragment within the coils, either because it is too large to be completely enveloped in the coils or, conversely, because the fragments are so small that they emerge from the coil loops, while the same close. In essence, basket devices cannot be used for the removal of particularly large or particularly small stone fragments.
A further drawback relates to the operational difficulty associated with the impossibility of enveloping the stone when the same is off the axis with respect to the opening of the basket coils.
In addition, after some steps and attempts to remove the lithiasis fragments, the basket operation is compromised, and this can lead to an extremely difficult release of the stone fragment, once it has been gripped, if it is considered too large to be extracted whole. Therefore, if the basket device operation is compromised, it must inevitably be replaced, with further economic expenditure. Moreover, the endoscopic maneuvers necessary to resolve this complication can be complex and cause in turn additional clinical complications.
Ultimately, all these technical and operational difficulties of the basket device involve a lengthening of the operating time.
US 2004/0019358 describes a device that includes an elongated element defining a hollow suction conduit. In particular, this elongated element is flexible lengthwise, is configured to be inserted within the operating channel of a ureteroscope and is also able to withstand the deformation caused by suction. More in detail, the proximal portion of the elongated element is in communication with a vacuum source able to provide the suction within the conduit, while the distal portion of the elongated element itself projects from the ureteroscope and is intended to come into contact with the object to be treated in the patient's body. US 2004/0019358 describes in detail the use of the elongated element for capturing, retaining, moving/removing a kidney stone when the latter is embedded in a tissue or is located in a part of the patient's body that is difficult to access using traditional instruments (baskets or grippers). However, in all these applications, it is provided that the conduit, defined within the elongated element, always and only acts as a suction conduit. In fact, US 2004/0019358 teaches at most to retract the elongated element from the ureteroscope and insert within the ureteroscope itself, as an alternative to the elongated element defining the suction conduit, another surgical instrument for removing the stone.
U.S. Pat. No. 5,102,415, WO 99/45835, US 2002/188313 and WO 2012/156924 relate to devices used in cardiology, not in the endourologic context. In particular, in the context of cardiology, the use of the endoscope is not involved and, therefore, the technical issues are different from those in the endourologic context, where the use of the endoscope is involved.
U.S. Pat. No. 6,375,651 describes a device that comprises a suction conduit and a conduit for energy transmission, which can be coextruded, attached to or separate from each other, or one inside the other. In addition, the casing of the device may accommodate a plurality of components, such as laser fibers, optical fibers and catheters and guide wires. However, in all the embodiments described in U.S. Pat. No. 6,375,651, there are always two conduits, one of suction and one for the laser fiber, which are separate from each other. In particular, the laser fiber conduit can also be placed within the suction conduit, but in any case they must be separate. Last but not least, the fact that the outer tubular casing, inside of which the suction conduit and the laser conduit are separately formed, internally has a particularly thick circular crown which has a particularly reduced flexibility lengthwise.
U.S. Pat. No. 7,540,868 describes a device provided with an elongated element connected to a suction tube and inside of which a laser fiber is inserted which is secured with a clip at the distal portion of the elongated element. The presence of the clip does not allow the removable insertion of the laser fiber and, in any case, does not allow the removable insertion of other gripping tools, such as grippers or the basket, used in endourologic treatments. In addition, U.S. Pat. No. 7,540,868 requires that the elongated element is connected to the suction connector via a suction tube, which is housed inside the casing of the device. Last but not least, the fact that the elongated element of U.S. Pat. No. 7,540,868 does not have a non-deformable inner lumen.
U.S. Pat. No. 4,692,139 describes a catheter for removing obstructions that are present in a biological channel that comprises an insertion sleeve (and not an endoscope) inside which a flexible vacuum tube is inserted which is connected with the proximal end thereof to a suction source. Moreover, a small tube is inserted within the suction tube for the injection of medical substances and an ultrasound probe. In this solution, the suction tube has on the outer surface a male thread that cooperates and engages with a corresponding female thread which is provided on the inner surface of the insertion sleeve in order to allow a controlled sliding of the suction tube inside the sleeve. Moreover, a locking ring of the distal end of the vacuum tube is provided at the distal tip of the sleeve in order to prevent the latter from protruding beyond the distal tip of the sleeve itself.
U.S. Pat. No. 5,417,697 describes a solution for removing a polyp from a patient's colon. This solution comprises a device for endoscopic surgery with an elongated tubular conduit insertable within a channel of an endoscope. In particular, at the distal end thereof, the tubular conduit has a cup-shaped portion from which a cauterization ring protrudes which is powered with electric current to cut the polyp from the patient. In addition, the tubular conduit is provided with suction to allow the polyp removed to enter within the conduit itself. As shown in the figures, the tubular conduit of U.S. Pat. No. 5,417,697 does not have a substantially non-deformable lumen, but indeed it must just be deformable in order to allow the entry of the polyp removed.
DE 19842113 describes a solution for extracting stents or blood clots from blood vessels. This solution comprises a first extraction catheter, which consists of a tubular conduit with three expandable portions at its distal tip which open to define a funnel. In particular, this extraction catheter is inserted through and entirely crosses a second introducer catheter, so that by protruding from the latter, the tip of the first one opens as a funnel. More in detail, the second introducer catheter consists of a cover sleeve, having smaller length than the extraction catheter and which is slidable along the latter. It is also possible to suction the clot within the extraction catheter and this means necessarily that the lumen of such a catheter should be deformable.
U.S. Pat. No. 5,417,697 and DE19842113 do not describe devices for the endourologic treatment and, in particular, it is clear that the deformability of the lumen of the tubular conduit of U.S. Pat. No. 5,417,697 of the extractor catheter of DE 19842113 makes these solutions unsuitable and incompatible with the needs and the suction values required in the endourologic context, for example for capturing and mobilizing the stones.